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surface treatment, coating and cleaning
Introduction Introduction Surface Technology outline Institut Teknologi Bandung1 Surface Technology Surfaces Tribology Surface Treatment Fabrication of Microelectronic devices Chapter 31 • Integrity • Structure • Texture • Roughness Chapter 32 • Friction • Wear • Lubrication Chapter 33 • Burnishing • Hardening • Deposition • Implantation • Coatings • Cleaning Chapter 34 Surface Treatment, Coating Surface Treatment, Coating and Cleaning and Cleaning Ir. Tri Prakosa, M. Eng. Proses Manufaktur II, Januari 2010 2 1. INTRODUCTION 1. INTRODUCTION Institut Teknologi Bandung3 1. Introduction 1. Introduction After a component is manufactured, all or parts of its surfaces may have to be processed further or coated in order to impart certain properties and characteristics. Surface treatment may be necessary to: { Improve resistance to wear, erosion, and indentation (slideways in machine tools, wear surfaces of machinery, and shafts, rolls, cams, and gears). { Control friction (sliding surfaces on tools, dies, bearings, and machine ways). { Reduce adhesion (electrical contacts). Institut Teknologi Bandung4 1. Introduction 1. Introduction { Improve lubrication (surface modification to retain lubricants). { Improve corrosion and oxidation resistance (sheet metals for automotive or other outdoor uses, gas turbine components, and medical devices). { Improve stiffness and fatigue resistance (bearings and multiple-diameter shafts with fillets). { Rebuild surfaces on worn components (worn tools, dies, and machine components). { Improve surface roughness (appearance, dimensional accuracy, and frictional characteristics). { Impart decorative features, color, or special surface texture. Institut Teknologi Bandung5 1. Introduction 1. Introduction Coating of critical surfaces is among important technological developments. Consider, for example, applications where temperatures are high and the environment is hostile, such as turbine blades and other components and surfaces of aerospace structures. Institut Teknologi Bandung6 1. Introduction 1. Introduction In advanced propulsion systems, for example, coatings have important functions. { First, they act as a thermal barrier to reduce the temperature to which parts are subjected. Engine components are expected to withstand temperatures as high as 1200 °C (2200 °F). Temperatures are high because the efficiency of gas turbines increases with increasing gas temperature. { Second, they protect surfaces from oxidation due to gases such as hot oxygen, and from hydrogen, used for cooling, which otherwise could form brittle compounds. Institut Teknologi Bandung7 1. Introduction 1. Introduction In addition to these physical and chemical requirements, coatings should also be: { Lightweight, thin, and resistant to damage; { have good adhesion; and { be easily applied to complex external and internal surfaces. Several techniques that are suitable and applicable to certain groups of materials have been developed (see next two Tables). Institut Teknologi Bandung8 Perlakuan Permukaan untuk Berbagai Logam Perlakuan Permukaan untuk Berbagai Logam Metal Treatment Aluminum Chrome plate; anodic coating, phosphate; chromate conversion coating Beryllium Anodic coating; chromate conversion coating Cadmium Phosphate; chromate conversion coating Die steels Boronizing; ion nitriding; liquid nitriding High-temperature steels Diffusion Magnesium Anodic coating; chromate conversion coating Mild steel Boronizing; phosphate; carburizing; liquid nitriding; carbonitriding; cyaniding Molybdenum Chrome plate Institut Teknologi Bandung9 Perlakuan Permukaan untuk Berbagai Logam Perlakuan Permukaan untuk Berbagai Logam Metal Treatment Nickel- and cobalt- base alloys Boronizing; diffusion Refractory metals Boronizing Stainless steel Vapor deposition; ion nitriding; diffusion; liquid nitriding; nitriding Steel Vapor deposition; chrome plate; phosphate; ion nitriding; induction hardening; flame hardening; liquid nitriding Titanium Chrome plate; anodic coating; ion nitriding Tool steel Boronizing; ion nitriding; diffusion; nitriding; liquid nitriding Zinc Vapor deposition; anodic coating; phosphate; chromate chemical conversion coating Institut Teknologi Bandung10 Sumber: After M. K. Gabel and D. M. Doorman in Wear Control Handbook, New York, ASME, 1980 p. 248. [...]... cleaning techniques for manufactured surfaces, particularly lubricant residues, before components are processed further, assembled, and the product is placed in service Environmental consideration: regarding the fluids used and the waste material from various surface treatment processes are among important factors to be considered 12 Institut Teknologi Bandung 2 MECHANICAL SURFACE TREATMENT AND COATING. .. Teknologi Bandung 3 CASE HARDENING AND HARD FACING 26 Institut Teknologi Bandung 3 Case Hardening and Hard Facing Surfaces may be hardened by thermal means in order to improve their frictional and wear properties, as well as resistance to indentation, erosion, abrasion, and corrosion The most common methods are described as: { { Case hardening, and Hard facing 27 Institut Teknologi Bandung 3.1... tools, and dies for hot metalworking Worn parts are also hard faced for extended use 33 Institut Teknologi Bandung 4 THERMAL SPRAYING 34 Institut Teknologi Bandung 4 Thermal Spraying In thermal spraying processes, coatings such as various metals and alloys, carbides, and ceramics are applied to metal surfaces by a spray gun with a stream of oxyfuel flame, electric arc, or plasma arc The coating. .. rod, or powder, and the droplets or particles impact the surfaces to be coated at speeds in the range of 100-1200 m/s (300-4000 ft/s) 35 Institut Teknologi Bandung 4 Thermal Spraying The surfaces to be sprayed should be cleaned and roughened to improve bond strength, which depends on the particular process and techniques used The coating has a layered structure of deposited material, and may include... COATING 13 Institut Teknologi Bandung 2 Mechanical Surface Treatment and Coating Several techniques are available for mechanically improving the surface properties of finished components The more common ones are described as follow: { { { { { Shot peening Roller burnishing and ballizing Explosive hardening Cladding (clad bonding) Mechanical plating 14 Institut Teknologi Bandung 2.1 Shot peening In... carbonitriding, cyaniding, nitriding, flame hardening, and induction hardening) were described in Section 4.10 and are summarized in Table 4.1 In addition to the common heat sources of gas and electricity, laser beams are also used as a heat source in surface hardening of both metals and ceramics 28 Institut Teknologi Bandung Outline of Heat Treatment Processes for Surface Hardening Process Metals hardened Carburizing... deposited on the surface by any of the welding techniques described in Chapters 27 and 28 A number of layers are usually deposited (weld overlay) Hard coatings of tungsten carbide and chromium and molybdenum carbides can also be deposited using an electric arc (spark hardening) 32 Institut Teknologi Bandung 3.2 Hard facing Hard-facing alloys are available as electrodes, rod, wire, and powder Typical... stresses on the surface, thus improving the fatigue life of the component This process is used extensively on shafts, gears, springs, oil-well drilling equipment, and jet-engine parts (such as turbine and compressor blades) 16 Institut Teknologi Bandung 2.2 Roller burnishing In roller burnishing, also called surface rolling, the surface of the component is cold worked by a hard and highly polished... sedikit lebih besar dibanding dimater lubang dalam (internal diameter) 20 Institut Teknologi Bandung 2.2 Roller burnishing Roller burnishing is used to improve the mechanical properties of surfaces, as well as the shape and surface finish of components It can be used either singly or in combination with other finishing processes, such as grinding, honing, and lapping Soft and ductile, as well as... modify the surface structure and its properties in order to impart these desirable characteristics The lecture begins with surface hardening techniques involving mechanical or thermal means and continues with different types of coatings that are applied by various means Some of these techniques are also used in the manufacture of semiconductor devices (next week lecture) 11 Institut Teknologi Bandung . 32 • Friction • Wear • Lubrication Chapter 33 • Burnishing • Hardening • Deposition • Implantation • Coatings • Cleaning Chapter 34 Surface Treatment, Coating Surface Treatment, Coating and Cleaning and. Teknologi Bandung12 2. MECHANICAL SURFACE 2. MECHANICAL SURFACE TREATMENT AND COATING TREATMENT AND COATING Institut Teknologi Bandung13 2. Mechanical Surface